WordPress Syntax Highlighter Plugins: Which to Install
Install Enlighter. It is the only syntax highlighter left in the WordPress plugin directory that is properly maintained, it handles the languages you are likely to post, and it styles its themes from CSS so you can restyle it without touching a template. Free, 4.8 out of 5 across 65 reviews, and the right answer for anyone publishing code regularly.
If you post code two or three times a year, install nothing. The block editor’s Code block preserves formatting and escapes HTML safely, which is enough for the occasional snippet and adds nothing to your page weight. Reach for a plugin when you want colour-coded languages, line numbers and copy buttons.
That is the whole decision. What follows is why the other options do not make the cut, and which ones to remove if you are already running them.
The one to install: Enlighter
Enlighter sits at version 4.7.0 with 10,000+ active installations, tested against WordPress 6.9.5, and it carries no untested warning. It is the only plugin here you can install today without inheriting a maintenance problem.
What you get: support for the common languages, a settings panel with a live preview so you can see a theme before committing to it, line numbers, and CSS-generated themes rather than hard-coded markup. There is a Gutenberg block and shortcode support, so it fits whichever editor you already use.
Check before you install: it requires WordPress 6.8 or higher and PHP 7.4 or higher. On older shared hosting that PHP requirement is the thing most likely to stop you.
The trade-off: highlighting happens in the browser, so every page carrying a snippet loads the highlighter’s JavaScript. On a site where code appears on a handful of posts, restrict it to those posts rather than loading it site-wide.
Get Enlighter on WordPress.org
Delete these if you are running them
Seven plugins commonly recommended for this job are no longer in the WordPress plugin directory. A withdrawn plugin keeps working and keeps looking healthy in your dashboard, but it receives no updates and nothing will prompt you to replace it. Two of the seven were closed over security issues, which makes them worth finding today rather than at the weekend.
• Prismatic – closed permanently on 9 August 2026 at its author’s request. This is the one to check for first: it was well regarded and well maintained right up to the closure, so nothing on your site will have visibly broken. Check on WordPress.org
• WP-GeSHi-Highlight – closed 18 March 2025 over a security issue. Last version 1.4.3. Check on WordPress.org
• WP Code Highlight.JS – closed 23 June 2019 over a security issue. Last version 0.6.3. Check on WordPress.org
• My Syntax Highlighter – closed 10 November 2022 for a guideline violation. Last version 2.58. Check on WordPress.org
• Syntax Highlighter for Theme/Plugin Editor – closed 10 November 2022 for a guideline violation. Last version 4.50. Check on WordPress.org
• Mivhak Syntax Highlighter – closed 15 February 2019 for a guideline violation. Last version 1.3.9. Check on WordPress.org
• AccessPress Custom CSS – closed 30 March 2023 for a guideline violation. Because it cannot be downloaded or updated from WordPress.org, any copy offered on a third-party mirror is unverified by definition. Do not install it from one. Check on WordPress.org
The same check works for anything else in your plugin list. Open wordpress.org/plugins/ followed by the plugin slug: a red closure notice means remove it, and a warning that it has not been tested with the latest three major releases means start looking for a replacement. Our guide to WordPress security plugins covers the wider habit of auditing what is installed.
The rest of the category, honestly
Five other highlighters are still in the directory. All five carry the untested warning, which means nobody has confirmed them against any of the last three major WordPress releases. None is broken today. None is a plugin to start a new site on.
| Plugin | Version | Active installs | Rating | Tested up to |
|---|---|---|---|---|
| Enlighter | 4.7.0 | 10,000+ | 4.8 / 5 (65) | 6.9.5, no warning |
| HTML Editor Syntax Highlighter | 2.4.4 | 50,000+ | 4.4 / 5 (110) | 6.5.0, untested warning |
| SyntaxHighlighter Evolved | 3.7.2 | 20,000+ | 4.3 / 5 (86) | 6.7.7, untested warning |
| Code Prettify | 1.5.1 | 1,000+ | 5 / 5 (18) | 6.0.14, untested warning |
| Simple Code Highlighter | 2.0 | 300+ | 4.7 / 5 (7) | 4.9.31, untested warning |
| FV Code Highlighter | 2.2.1 | 10+ | 4 / 5 (2) | 5.2.26, untested warning |
HTML Editor Syntax Highlighter
This one does a different job from the others: it highlights code inside the WordPress admin, using the CodeMirror library, including the theme and plugin file editors. That is where its 50,000+ installations come from. Ctrl+S to save, cursor position restored after a reload and a fullscreen mode are the extras people keep it for.
Worth knowing: tested only to WordPress 6.5.0 and carrying the untested warning. If you are editing theme files from the admin regularly, a proper code editor and SFTP is the better habit anyway.
HTML Editor Syntax Highlighter on WordPress.org
SyntaxHighlighter Evolved
The long-standing default for WordPress code blocks, originally by Alex Mills with contributions from Automattic. It needs almost no configuration, detects code blocks automatically and ships a handful of themes.
Worth knowing: version 3.7.2, tested only to WordPress 6.7.7, untested warning on the listing. If you have inherited a site that already uses its shortcodes, leaving it alone is reasonable. Switching to it from scratch is not.
SyntaxHighlighter Evolved on WordPress.org
Code Prettify, Simple Code Highlighter and FV Code Highlighter
Code Prettify is a light wrapper that targets every code and pre tag on your site automatically, so you write plain HTML and it does the formatting. Its 5 out of 5 rating comes from only 18 reviews, and its last release predates several major WordPress versions.
Simple Code Highlighter wraps Google’s code-prettify script behind an editor toolbar button, for people who would rather not learn shortcode syntax. It is tested only to WordPress 4.9.31 and is down to 300+ installations.
FV Code Highlighter handles PHP, JavaScript, CSS, XML and HTML with a Dreamweaver-style colour scheme and allows code tags in comments. It is tested only to WordPress 5.2.26 and down to 10+ installations, which tells its own story.
All three still work. None of them is a plugin to build a publishing habit on.
If what you actually want is custom CSS
These are different jobs and they get confused often. A syntax highlighter formats code snippets so your readers can read them. A custom CSS plugin adds styles to your own site.
If it is the second one you want, try the Additional CSS panel in the WordPress Customizer or your block theme’s style settings first. Both are built in and neither needs a plugin. If you want a dedicated interface, Simple Custom CSS by John Regan is on 100,000+ sites at 4.7 out of 5 from 159 reviews, though its listing is tested only to WordPress 6.7.7 and carries the untested warning. Our roundup of the CSS and JavaScript Toolbox covers the heavier options.
Simple Custom CSS on WordPress.org
Frequently asked questions
Which syntax highlighter plugin should I install?
Enlighter. It is the only one in the WordPress plugin directory that is actively maintained: version 4.7.0, 10,000+ active installations, a 4.8 out of 5 rating from 65 reviews, and tested against WordPress 6.9.5 with no untested warning. Every other syntax highlighter in the directory either carries that warning or has been withdrawn.
Do I even need a syntax highlighter plugin?
Often not. The WordPress block editor includes a Code block that preserves formatting and escapes HTML safely, which is enough for the occasional snippet and adds nothing to your page weight. A dedicated highlighter earns its place when you publish code regularly and want colour-coded languages, line numbers and copy buttons.
What does the untested with the latest 3 major releases warning mean?
WordPress.org shows that banner when a plugin’s author has not confirmed compatibility with any of the last three major WordPress releases. It does not mean the plugin is broken today. It does mean nobody is checking it against new versions, so it can break at any release. Treat it as a signal to plan a replacement rather than an emergency.
Prismatic has disappeared from the plugin directory. What should I use instead?
Enlighter is the closest maintained equivalent. Prismatic was closed permanently on 9 August 2026 at its author’s request, so it can no longer be downloaded or updated from WordPress.org. If it is still installed on your site it will keep running and will never be patched again, which is the reason to move rather than wait.
Is a custom CSS plugin the same thing as a syntax highlighter?
No. A custom CSS plugin lets you add styles to your own site. A syntax highlighter formats code snippets so your readers can read them. If what you want is to add CSS to your theme, use the Additional CSS panel in the WordPress Customizer or your block theme’s style settings before reaching for a plugin.
In short
Install Enlighter, or use the block editor’s Code block and install nothing at all. If you are running one of the seven withdrawn plugins, replace it this week rather than next quarter. And if you are weighing up the block editor against the classic one more broadly, our comparison of Gutenberg and the Classic Editor covers that choice properly.
More of our WordPress plugin coverage is here.
